One of the distinct challenges faced by emerging adults with HIV is the transition of their care from their long- term pediatric HIV provider to treatment within an adult HIV program. While conceptually the transition from pediatric to adult care may seem straightforward, the reality is that the transition often is a very difficult process. The consequences of an unsuccessful transition can range from difficult to catastrophic. The Adolescent to Adult Patient-centered HIV Transition (ADAPT) Study is a randomized trial of innovative interventions targeting gaps in care that are major drivers of loss in the ART continuum of care cascade among adolescents and increasing missed opportunities to engage adolescents into care. The specific aims of ADAPT are: (a) to inform strategies for transition services in resource-limited settings; (b) to examine the developmental, clinical, and other factors that predict a successful transition; and (c) to gain fundamental insight on implementation barriers among African adolescents through the application of the ego-network defined social support that will inform targets for structured intervention. Our multi-PI team includes strong complementary expertise in pediatric and adolescent HIV care, epidemiology, and social science. ADAPT will be conducted in central, southern, and northern Nigeria at selected PEPFAR sites supported by the Institute of Human Virology, Nigeria. To address Aim 1 we will conduct six focus groups including: Adolescent patients, parents and health care providers. To address aim 2, we will conduct a cluster randomized clinical trial. The two interventions are based on prior evidence-informed engagement strategies: 1) educational interventions and 2) interventions that use a peer transition advocate who prepares the adolescent and their parents for transition. We will enroll 300 patients (150 patients in each arm). The sites will be randomized to an intervention. The primary outcome will be successful transition, keeping two follow-up appointments within a nine months period following transition. Secondary outcomes, as recommended by focus group participants will also be measured. To examine the potential role of social network components and characteristics of both egos and alters on primary outcomes, a Generalized Estimating Equation (GEE) approach will be used to explore the associations between primary outcomes and factors at the ego, alter, and network levels. The finding from this study will guide institution of best practices for transitioning adolescents in Nigeria and other countries lower and middle income countries with similar challenges and potential for high impact.